Robot cleaners are devices for doing the cleaning work by absorbing foreign materials like dust from the floor while driving a cleaning area itself without any help from a user. They clean the area while turning their course, by determining a distance to an obstacle like furniture, office equipment, walls, etc. in the cleaning area and driving left-wheel and right-wheel motors selectively.
The robot cleaner has an inlet on its bottom to absorb dust on the floor. On the side of the inlet, a main brush is rotationally mounted to pick up dust on the floor. Side brushes may further be included in the robot cleaner. They are attached to either side of the front of the robot cleaner, sweeping dust or things, out of reach to the main brush, toward the center. The dust or things swept by the side brushes toward the center may be picked up by the main brush and absorbed through the inlet. Such side brushes may expand the cleaning area of the robot cleaner.